Aromatic imide and aromatic methylidynetrissulfonyl compounds and method of making

ABSTRACT

A method is provided for making aromatic-imide and aromatic-methylidynetrissulfonyl species by reaction of aromatic species with a reactant according to formula (I):  
     (X—SO 2 —) m -QH—(—SO 2 —R 1 ) n   (I)  
     wherein Q is C or N; wherein each X is independently selected from the group consisting of halogens, typically F or Cl; wherein each R 1  is independently selected from the group consisting of aliphatic and aromatic groups, which may or may not be saturated, unsaturated, straight-chain, branched, cyclic, heteroatomic, polymeric, halogenated, fluorinated or substituted; wherein m is greater than 0; wherein m+n=2 when Q is N; and wherein m+n=3 when Q is C. Ar may be derived from an aromatic polymeric compound. In addition, compounds are provided according to the formula: (Ar—SO 2 —) m -QH—(—SO 2 —R 1 ) n  wherein R 1  comprises a highly acidic group selected from sulfonic acid, carboxylic acid and phosphonic acid, and Ar is derived from an aromatic compound.

FIELD OF THE INVENTION

[0001] This invention relates to the synthesis of aromatic-imide andaromatic-methylidynetrissulfonyl species. The synthesis proceeds byreaction of aromatic species, including aromatic polymers, with areactant according to the formula: (X—SO₂—)_(m)-QH—(—SO₂—R₁)_(n);wherein Q is C or N and X is a halogen. The present inventionadditionally relates to compounds according to the formula:(Ar—SO₂—)_(m)-QH—(—SO₂—R₁)_(n) wherein R₁ comprises a highly acidicgroup selected from sulfonic acid, carboxylic acid and phosphonic acid,which may be particularly useful as electrolytes.

BACKGROUND OF THE INVENTION

[0002] U.S. Pat. No. 6,090,895 discloses crosslinked polymers havingimide crosslinking groups and methods of crosslinking polymers to formimide crosslinking groups. These crosslinked polymers may be useful aspolymer electrolyte membranes (PEM's) in fuel cells. The referencediscloses methods of making imides by reaction of acid halides withamides, including aromatic acid halides and aromatic amides. The acidhalides may be formed by haloacidification, e.g., chlorosulfonation, ofaromatic species.

[0003] U.S. Pat. No. 6,063,522 discloses electrolytes for use inelectrochemical cells that include imide and methide conductive salts.The reference also discloses methods of making imides by reaction ofacid halides with amides.

[0004] U.S. Pat. No. 4,505,997 discloses syntheses of imides by reactionof sulfonate and sulfonic anhydride species with urea. The referencediscloses electrolytes comprising imide functional groups.

[0005] U.S. Pat. No. 5,652,072 discloses syntheses of imides by reactionof sulfonyl halide species with ammonia or with amide species. Thereference discloses electrolytes comprising imide functional groups.

[0006] U.S. Pat. No. 5,072,040 discloses syntheses of imides by reactionof sulfonyl halide species with nitride species. The reference suggeststhe use of imide functional species in electrolytes.

[0007] U.S. Pat. No. 5,514,493 discloses syntheses of imides by reactionof sulfonyl halide species with ammonia or with amide species. Thereference discloses electrolytes comprising imide functional groups.

[0008] U.S. Pat. No. 5,463,005 discloses perfluorinated monomers andpolymers comprising sulfonyl and carbonyl imide groups for use as solidpolymer electolytes. The reference discloses a synthesis of imides byreaction of amides with hexamethyldisilazine followed by reaction with asulfonyl fluoride.

[0009] Argyropoulos & Lenk, “Condensation Products fromImidobis(sulfuryl Chloride),” J. Ap. Polym. Sci. v. 26, pp. 3073-3084(1981), discloses reactions of imidobis(sulfuryl chloride).

SUMMARY OF THE INVENTION

[0010] Briefly, the present invention provides a method of makingaromatic-imide and aromatic-methylidynetrissulfonyl species by reactionof aromatic species with a reactant according to formula (I):

(X—SO₂—)_(m)-QH—(—SO₂—R₁)_(n)  (I)

[0011]  wherein Q is C or N; wherein each X is independently selectedfrom the group consisting of halogens, typically F or Cl; wherein eachR₁ is independently selected from the group consisting of aliphatic andaromatic groups, which may or may not be saturated, unsaturated,straight-chain, branched, cyclic, heteroatomic, polymeric, halogenated,fluorinated or substituted; wherein m is greater than 0; wherein m+n=2when Q is N; and wherein m+n=3 when Q is C. Ar may be derived from anaromatic polymeric compound.

[0012] In another aspect, the present invention concerns compoundsaccording to formula (V), which compounds may be made using the methodaccording to the present invention:

(Ar—SO₂—)_(m)-QH—(—SO₂—R₁)_(n)  (V)

[0013]  wherein Ar is an aromatic group derived from an aromaticcompound; wherein Q is C or N; wherein each R₁ is independently selectedfrom the group consisting of aliphatic and aromatic groups, which may ormay not be saturated, unsaturated, straight-chain, branched, cyclic,heteroatomic, polymeric, halogenated, fluorinated or substituted;wherein at least one R₁ contains at least one highly acidic groupselected from sulfonic acid, carboxylic acid and phosphonic acid;wherein m and N are each greater than 0; wherein m+n=2 when Q is N; andwherein m+n=3 when Q is C.

[0014] What has not been described in the art, and is provided by thepresent invention, is a simple method of synthesizing aromatic imidesand aromatic methylidynetrissulfonyl species by direct substitution ofaromatic species, including pre-existing aromatic polymers, by use ofthe reactants described herein.

[0015] In this application:

[0016] “highly acidic” means having a pKa<5;

[0017] “highly halogenated” means containing halogen in an amount of 40wt % or more, but typically 50 wt % or more, and more typically 60 wt %or more; and

[0018] “highly fluorinated” means containing fluorine in an amount of 40wt % or more, but typically 50 wt % or more, and more typically 60 wt %or more; and

[0019] “substituted” means, for a chemical species, substituted byconventional substituents which do not interfere with the desiredproduct or process, e.g., substituents can be alkyl, alkoxy, aryl,phenyl, halo (F, Cl, Br, I), cyano, nitro, etc.

[0020] It is an advantage of the present invention to provide a simpleand convenient synthetic route to aromatic-imide andaromatic-methylidynetrissulfonyl electrolytes, including solid polymerelectrolytes, which are useful in electrochemical devices such asbatteries and fuel cells.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0021] The present invention provides a method of making aromatic-imideand aromatic-methylidynetrissulfonyl species by reaction of aromaticspecies with a reactant according to formula (I):

(X—SO₂—)_(m)-QH—(—SO₂—R₁)_(n)  (I)

[0022]  wherein Q is C or N; wherein each X is independently selectedfrom the group consisting of halogens; wherein each R₁ is independentlyselected from the group consisting of wherein R₁ is selected from thegroup consisting of aliphatic and aromatic groups, which may or may notbe saturated, unsaturated, straight-chain, branched, cyclic,heteroatomic, polymeric, halogenated, fluorinated or substituted;wherein m is greater than 0; wherein m+n=2 when Q is N; and whereinm+n=3 when Q is C.

[0023] For the reactant according to formula (I), Q may be C or N but ismore typically N. Where Q is N, m may be 1 or 2. Where Q is C, m may be1, 2 or 3, but is typically 1 or 2. Each X is a halogen, typically F orCl, and most typically Cl.

[0024] R₁ is any suitable group that does not interfere with thesynthesis according to the present invention and which provides aproduct having desired characteristics. Each R₁ may be aromatic oraliphatic; may be saturated or unsaturated; may be straight-chain,branched, or cyclic; may be heteroatomic or non-heteroatomic; maycomprise a polymer; and may additionally be substituted including inparticular halogenation, including in particular fluorination. R₁typically comprises between 0 and 20 carbon atoms, more typically 0 to 8carbon atoms, more typically 0 to 4 carbon atoms. Where the productspecies is intended for use as an electrolyte, R₁ is typically highlyhalogenated, more typically highly fluorinated, more typicallyperhalogenated, and most typically perfluorinated. Where the productspecies is intended for use as an electrolyte, R₁ is typically selectedfrom: trihalomethyl, pentahaloethyl, heptahalopropyl, and nonahalobutyl,more typically where halogen substituents are selected from F and Cl.More typically, R₁ is selected from: trifluoromethyl, pentafluoroethyl,heptafluoropropyl, and nonafluorobutyl, most typically trifluoromethyl.

[0025] R₁ may advantageously contain additional highly acidic groups,typically including sulfonic acids, carboxylic acids and phosphonicacids, most typically sulfonic acid groups. R₁ may contain the highlyacidic group according to formula (IV):

[0026]  wherein Q and X are as defined above, wherein R_(1′) is selectedfrom the same group as R₁ defined above except that R_(1′) is typicallynot another group according to formula (IV), wherein p+q=1 when Q is N;and wherein p+q=2 when Q is C.

[0027] Alternately, R₁ may advantageously contain additionalaromatic-binding groups such as sulfonyl halides or groups according toformula (IV) above where p>0. Where R₁ contains additionalaromatic-binding groups and Ar is polymeric, crosslinking may result.

[0028] The reactant according to formula (I) above may be synthesized bymethods such as described in Roesty & Giere, “Darstellung vonN-Trifluormethanesulfonyl-sulfonylfluoridamid und einige reaktionen,”Inorg. Nucl. Chem. v. 7, pp. 171-175 (1971) or Becke-Goehring & Fluck,“Imidodisulfuric acid chloride,” Inorganic Synthesis, v. 8, pp. 105-107(1966)), which are incorporated by reference herein, or by methodsanalogous thereto, or by other methods known in the art.

[0029] Ar may be polymeric or non-polymeric. Polymeric examples of Arinclude polymers with aromatic groups in the polymer backbone, such aspolyphenylene oxide (PPO), and polymers with pendent aromatic groups,such as polystyrene. Aromatic polymers which may be useful as Ar in thepresent reaction include PPO, polystyrene, polyether ether ketone(PEEK), polyether ketone (PEK) and polysulfone and substitutedderivatives thereof. Where m is greater than 1, a crosslinked productmay result. Mixtures of reactants may be used to control the degree ofcrosslinking, such as mixtures of m=1 reactants and m=2 reactants.

[0030] Non-polymeric examples of Ar include aromatic groups having 5 to20 carbon atoms, including monocyclic and polycyclic species andincluding heteroatomic and non-heteroatomic species. Additional aromaticspecies which may be useful as Ar in the present reaction include:benzene, toluene, naphthalene, anthracene, phenanthrene, fluorene,biphenyl, terphenyl, stillbene, indene, chrysene, pyrene, tetracene,fluoranthrene, coronene, pyridine, pyridazine, pyrimidine, pyrazine,imidazole, pyrazole thiazole, oxazole, triazole, quinoline, benzofuran,indole, benzothiophene, carbazole, and aromatic isomers and substitutedderivatives thereof.

[0031] The aromatic reactant and the reactant according to formula (I)may be combined under any suitable reaction conditions. The reactionconditions are advantageously anhydrous. The reactants may be combinedin solvent or neat. Where Ar is polymeric, the reactants are typicallycombined in an inert solvent such as CCl₄. Alternately, the reactant maybe imbibed into the polymer, either neat or by use of a solvent. In thiscase, the polymer may be preformed into a membrane or other usefulshape. The reaction mixture is typically heated. Catalyst may be addedbut is not necessary.

[0032] The method of the present invention may be used to make a classof aromatic-imide and aromatic-methylidynetrissulfonyl species bearingadditional acidic functions which may be useful as electrolytes,according to formula (V):

(Ar—SO₂—)_(m)-QH—(—SO₂—R₁)_(n)  (V)

[0033]  wherein Ar is an aromatic group derived from an aromaticcompound; wherein Q is C or N; wherein each R₁ is independently selectedfrom the group consisting of aliphatic and aromatic groups, which may ormay not be saturated, unsaturated, straight-chain, branched, cyclic,heteroatomic, polymeric, halogenated, fluorinated or substituted;wherein at least one R₁ contains at least one additional highly acidicgroup; wherein m is greater than 0; wherein n is greater than 0; whereinm+n=2 when Q is N; and wherein m+n=3 when Q is C. Typically, Q is N, m=1and n=1. Typically, the additional acid group of R₁ is selected fromsulfonic acids, carboxylic acids, phosphonic acids, imides, andmethylidynetrissulfonyl groups, most typically sulfonic acid groups. R₁may advantageously comprise an aromatic group. R₁ may advantageouslycomprise an aromatic group according to the formula:—PhY_(5-v)(SO₂H)_(v) where Ph is phenyl; each Y is independentlyselected from H, F, C₁ and CH₃; and v is 1, 2 or 3, more typically 1 or2, most typically 1.

[0034] Compounds according to formula (V) include those wherein Ar isderived from an aromatic polymeric compound. In one embodiment, Ar is anaromatic polymer bearing numerous pendent imide ormethylidynetrissulfonyl groups according to formula (V). Suitablepolymers may include polymers with aromatic groups in the polymerbackbone, such as polyphenylene oxide (PPO), and polymers with pendentaromatic groups, such as polystyrene. Aromatic polymers which may beuseful as Ar in the present reaction include PPO, polystyrene, polyetherether ketone (PEEK), polyether ketone (PEK) and polysulfone andsubstituted derivatives thereof.

[0035] This invention is useful in the synthesis of aromatic-imide andaromatic-methylidynetrissulfonyl electrolytes, including solid polymerelectrolytes, which are useful in electrochemical devices such asbatteries and fuel cells.

[0036] Objects and advantages of this invention are further illustratedby the following examples, but the particular materials and amountsthereof recited in these examples, as well as other conditions anddetails, should not be construed to unduly limit this invention.

EXAMPLES

[0037] Unless otherwise noted, all reagents were obtained or areavailable from Aldrich Chemical Co., Milwaukee, Wis., or may besynthesized by known methods.

Example 1

[0038]

[0039] (ClSO₂)₂NH (1 g) (synthesized according to Becke-Goehring &Fluck, “Imidodisulfuric acid chloride,” Inorganic Synthesis, v. 8, pp.105-107 (1966)) was mixed with 5 g of toluene and heated to 100° C.under nitrogen for 24 hours. The solution was then dried on a rotaryevaporator to give an oily white solid. To this was added 5 ml of waterand then 40 ml of 1 M LiOH. The resulting solution was stirred overnightand filtered, and evaporation of the solvent gave a white solid. Thiswas stirred overnight with 100 ml of THF and filtered. Evaporation gave2.10 g of a white solid identified by NMR as mixture of the ortho andpara isomers of the lithium salt of the corresponding bis aromatic imide(compound 1).

Example 2

[0040]

[0041] CF₃SO₂NHSO₂Cl (0.86 g) (synthesized according to Roesty & Giere,“Darstellung von N-Trifluormethanesulfonyl-sulfonylfluoridamid undeinige reaktionen,” Inorg. Nucl. Chem. v. 7, pp. 171-175 (1971)) wasdissolved in 5 g of benzene. The resulting solution was refluxed for 18hours under nitrogen and the solvent was removed by vacuum. Theremaining solid was mixed with 5 ml of 5 M LiOH and dried. The solidswere then washed with 10 ml of THF, filtered and the THF was removed byvacuum to give a light yellow solid. NMR (¹H and ¹⁹F) showed this to beCF₃SO₂—N^(—)—SO₂(C₆H₅) Li⁺, (Li salt of compound 2) along with smalleramounts of CF₃SO₂NH₂ and benzene sulfonate byproducts.

Example 3

[0042]

[0043] Polymethyl styrene (0.25 g)(obtained from Aldrich Chemical Co.,Milwaukee, Wis.) was dissolved in 2.5 ml of dry CCl₄. To this was added0.78 g of CF₃SO₂NHSO₂Cl (sourced as above) and the resulting solutionwas heated to 80° C. under nitrogen. After about 15 minutes the solutionbecame viscous and an additional 1 ml of CCl₄ was added. The solutionwas heated to 80° C. for an additional 2 hours and then the solvent wasremove under vacuum. To the dried product was added 10 ml of water andit was allowed to stir overnight. The resulting white solid (0.34 g) wasisolated by filtration and a portion was dissolved in 1 M NaOH in D₂Ofor NMR analysis. Fluorine NMR showed a broad peak at −74.7 ppm due tothe Na salt of the desired polymer (3) and a smaller, sharper peak at−76.7 ppm, attributed to CF₃SO₂NH₂ formed from hydrolysis of thestarting acid by residual water.

[0044] Various modifications and alterations of this invention willbecome apparent to those skilled in the art without departing from thescope and principles of this invention, and it should be understood thatthis invention is not to be unduly limited to the illustrativeembodiments set forth hereinabove. All publications and patents areherein incorporated by reference to the same extent as if eachindividual publication or patent was specifically and individuallyindicated to be incorporated by reference.

We claim:
 1. A method comprising a step of heating one or more aromaticcompounds Ar in the presence of a first reactant so as to form one ormore product compounds of Ar and said first reactant, said productcompounds containing aromatic-sulfonimide oraromatic-methylidynetrissulfonyl bonds, wherein said first reactant is acompound according to formula (I): (X—SO₂—)_(m)-QH—(—SO₂—R₁)_(n)  (I)wherein Q is C or N; wherein each X is independently selected from thegroup consisting of halogens; wherein each R₁ is independently selectedfrom the group consisting of aliphatic and aromatic groups, which may ormay not be saturated, unsaturated, straight-chain, branched, cyclic,heteroatomic, polymeric, halogenated, fluorinated or substituted;wherein m is greater than 0; wherein m+n=2 when Q is N; and whereinm+n=3 when Q is C.
 2. The method according to claim 1 wherein Ar is anaromatic polymeric compound.
 3. The method according to claim 1 whereinQ is N and said product compounds contain aromatic-sulfonimide bonds. 4.The method according to claim 2 wherein Q is N and said productcompounds contain aromatic-sulfonimide bonds.
 5. The method according toclaim 3 wherein m=1 and said product compounds are compounds accordingto formula (II) Ar—SO₂—NH—SO₂—R₁  (II) wherein Ar is an aromatic groupderived from an aromatic compound; and wherein R₁ is selected from thegroup consisting of aliphatic and aromatic groups, which may or may notbe saturated, unsaturated, straight-chain, branched, cyclic,heteroatomic, polymeric, halogenated, fluorinated or substituted.
 6. Themethod according to claim 4 wherein m=1 and said product compounds arecompounds according to formula (II) Ar—SO₂—NH—SO₂—R₁  (II) wherein Ar isan aromatic group derived from an aromatic polymeric compound; andwherein R₁ is selected from the group consisting of aliphatic andaromatic groups, which may or may not be saturated, unsaturated,straight-chain, branched, cyclic, heteroatomic, polymeric, halogenated,fluorinated or substituted.
 7. The method according to claim 3 whereinm=2 and said product compounds are compounds according to formula (III)Ar—SO₂—NH—SO₂—Ar  (III) wherein each Ar is an aromatic group derivedfrom an aromatic compound, which may be the same or different.
 8. Themethod according to claim 1 wherein each R₁ is highly fluorinated. 9.The method according to claim 5 wherein each R₁ is highly fluorinated.10. The method according to claim 6 wherein each R₁ is highlyfluorinated.
 11. The method according to claim 5 wherein each Ar isselected from the group consisting of aromatic groups having 5 to 20carbon atoms.
 12. The method according to claim 7 wherein each Ar isselected from the group consisting of aromatic groups having 5 to 20carbon atoms.
 13. The method according to claim 1 wherein each X isindependently selected from the group consisting of fluorine andchlorine.
 14. The method according to claim 5 wherein each X isindependently selected from the group consisting of fluorine andchlorine.
 15. The method according to claim 6 wherein each X isindependently selected from the group consisting of fluorine andchlorine.
 16. The method according to claim 7 wherein each X isindependently selected from the group consisting of fluorine andchlorine.
 17. The method according to claim 1 wherein at least one R₁contains at least one highly acidic group.
 18. The method according toclaim 1 wherein at least one R₁ contains at least one highly acidicgroup selected from the group consisting of: sulfonic acid, carboxylicacid, phosphonic acid, imide, and methylidynetrissulfonyl groups. 19.The method according to claim 1 wherein at least one R₁ contains atleast one sulfonic acid group.
 20. The method according to claim 1wherein at least one R₁ contains at least one group according to formula(IV):

wherein each Q and X are as defined above, wherein each R_(1′) isindependently selected from the group consisting of aliphatic andaromatic groups, which may or may not be saturated, unsaturated,straight-chain, branched, cyclic, heteroatomic, polymeric, halogenated,fluorinated or substituted; wherein p+q=1 when Q is N; and wherein p+q=2when Q is C.
 21. The method according to claim 20 wherein Ar is anaromatic polymeric compound.
 22. The method according to claim 21wherein Q is N and said product compounds contain aromatic-sulfonimidebonds.
 23. A compound according to formula (V):(Ar—SO₂—)_(m)-QH—(—SO₂—R₁)_(n)  (V) wherein Ar is an aromatic groupderived from an aromatic compound; wherein Q is C or N; wherein each R₁is independently selected from the group consisting of aliphatic andaromatic groups, which may or may not be saturated, unsaturated,straight-chain, branched, cyclic, heteroatomic, polymeric, halogenated,fluorinated or substituted; wherein at least one R₁ contains at leastone highly acidic group selected from the group consisting of: sulfonicacid, carboxylic acid and phosphonic acid; wherein m is greater than 0;wherein n is greater than 0; wherein m+n=2 when Q is N; and whereinm+n=3 when Q is C.
 24. A compound according to claim 23 wherein Q is N,m=1 and n=1.
 25. A compound according to claim 23 wherein at least oneR₁ contains at least one sulfonic acid group.
 26. A compound accordingto claim 23 wherein Ar is derived from an aromatic polymer.
 27. Acompound according to claim 24 wherein Ar is derived from an aromaticpolymer.
 28. A compound according to claim 25 wherein Ar is derived froman aromatic polymer.
 29. A compound according to claim 23 wherein R₁comprises an aromatic group according to the formula:—PhY_(5-v)(SO₂H)_(v); wherein Ph is phenyl; wherein each Y isindependently selected from H, F, Cl and CH₃; and wherein v is 1, 2 or3.
 30. A compound according to claim 27 wherein R₁ comprises an aromaticgroup according to the formula: —PhY_(5-v)(SO₂H)_(v); wherein Ph isphenyl; wherein each Y is independently selected from H, F, Cl and CH₃;and wherein v is 1, 2 or 3.